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111.
112.
Tree-ring reconstructed dry season rainfall in Guatemala 总被引:1,自引:0,他引:1
Anchukaitis Kevin J. Taylor Matthew J. Leland Caroline Pons Diego Martin-Fernandez Javier Castellanos Edwin 《Climate Dynamics》2015,45(5-6):1537-1546
Climate Dynamics - Drought in Guatemala has negative consequences for agriculture and potable water supplies, particularly in regions of the country with highly seasonal rainfall. General... 相似文献
113.
Integrated assessment of smallholder farming’s vulnerability to drought in the Brazilian Semi-arid: a case study in Ceará 总被引:1,自引:0,他引:1
Diego Pereira Lindoso Juliana Dalboni Rocha Nathan Debortoli Izabel Ibiapina Parente Flávio Eiró Marcel Bursztyn Saulo Rodrigues-Filho 《Climatic change》2014,127(1):93-105
Smallholder farming is among the most vulnerable sectors due to its great social and economic sensitivity. Despite future climate change, current climate variability is already an issue of concern that justifies adaptation efforts. In Brazil, the Semi-Arid Region is a climate hotspot, well known for both historic socioeconomic setbacks, and agriculture failures caused by dry spells and severe droughts. In 2010, the Brazilian government enacted the National Policy on Climate Change, which states as one of its key goals the identification of vulnerabilities and the adoption of adequate measures of adaptation to climate change. The improvement of vulnerability assessment tools is a response to the growing demand of decision makers for regular information and indicators with high spatial and temporal resolution. This article aims at undertaking a comparative assessment of smallholder farming’s vulnerability to droughts. An integrated assessment system has been developed and applied to seven municipalities located in the Brazilian Semi-Arid Region (within the State of Ceará). Results show regional vulnerability contrasts driven by institutional and socioeconomic factors, beyond climatic stressors. 相似文献
114.
Avellaneda PM Englehardt JD Olascoaga J Babcock EA Brand L Lirman D Rogge WF Solo-Gabriele H Tchobanoglous G 《Marine pollution bulletin》2011,62(10):2157-2169
A relative risk assessment of biosolids disposal alternatives for cruise ships is presented in this paper. The area of study encompasses islands and marine waters of the Caribbean Sea. The objective was to evaluate relative human health and ecological risks of (a) dewatering/incineration, (b) landing the solids for disposal, considering that in some countries land-disposed solids might be discharged in the near-shore environment untreated, and (c) deep ocean disposal. Input to the Bayesian assessment consisted of professional judgment based on available literature and modeling information, data on constituent concentrations in cruise ship biosolids, and simulations of constituent concentrations in Caribbean waters assuming ocean disposal. Results indicate that human health and ecological risks associated with land disposal and shallow ocean disposal are higher than those of the deep ocean disposal and incineration. For incineration, predicted ecological impacts were lower relative to deep ocean disposal before considering potential impacts of carbon emissions. 相似文献
115.
Luca Caricchi Anne Pommier Mattia Pistone Jonathan Castro Alain Burgisser Diego Perugini 《Bulletin of Volcanology》2011,73(9):1245-1257
Experiments have been performed to determine the effect of deformation on degassing of bubble-bearing melts. Cylindrical specimens
of phonolitic composition, initial water content of 1.5 wt.% and 2 vol.% bubbles, have been deformed in simple-shear (torsional
configuration) in an internally heated Paterson-type pressure vessel at temperatures of 798–848 K, 100–180 MPa confining pressure
and different final strains. Micro-structural analyses of the samples before and after deformation have been performed in
two and three dimensions using optical microscopy, a nanotomography machine and synchrotron tomography. The water content
of the glasses before and after deformation has been measured using Fourier Transform Infrared Spectroscopy (FTIR). In samples
strained up to a total of γ ∼ 2 the bubbles record accurately the total strain, whereas at higher strains (γ ∼ 10) the bubbles
become very flattened and elongate in the direction of shear. The residual water content of the glasses remains constant up
to a strain of γ ∼ 2 and then decreases to about 0.2 wt.% at γ ∼ 10. Results show that strain enhances bubble coalescence
and degassing even at low bubble volume-fractions. Noticeably, deformation produced a strongly water under-saturated melt.
This suggests that degassing may occur at great depths in the volcanic conduit and may force the magma to become super-cooled
early during ascent to the Earth’s surface potentially contributing to the genesis of obsidian. 相似文献
116.
Barbara Borzi Fabio Dell��Acqua Marta Faravelli Paolo Gamba Gianni Lisini Mauro Onida Diego Polli 《Bulletin of Earthquake Engineering》2011,9(2):675-690
The aim of this paper is to disseminate knowledge in the seismic science community about a possible tool which is not largely
popular, despite its potential usefulness. In this paper it will be shown how satellite remotely sensed images may represent
a powerful source of information where traditional sources of information are unable to deliver it, or at least to do so timely.
Even when traditional information flow can ensure delivery, an advantage may still be found in terms of sooner availability
and smaller amount of labour required. In the case shown here a vulnerability study was made on a vast industrial area in
the gulf of Siracusa, Sicily, Italy. A series of concurrent factors made it particularly troublesome to obtain information
on the structures found in the site (tanks, pipes, chimneys, roads, ...), required to suitably carry out the study. Satellite
images were then acquired to obtain the information needed. Processing of the images was carried out relying on in-house software
formerly developed for similar information extraction issues, and integrated with new, specifically developed elements, some
pieces of information were obtained useful for seismic risk evaluation. In particular, location, footprint, elevation of significant
structures (e.g. tanks, chimneys) could be evaluated, obtaining results in a format compatible with the most widespread GIS
(Geographic Information System) standards. Such compatibility allowed a considerable savings on labour time required to lay
a GIS of the area, which is a fundamental tool for risk and vulnerability analyses. 相似文献
117.
118.
Diego Nicolas Iaffa F. Sàbat D. Bello O. Ferrer R. Mon A.A. Gutierrez 《Journal of South American Earth Sciences》2011,31(4):457-474
The Tucumán foreland basin is bounded by: 1) basement cored ranges with elevations over 6000 m in the west; 2) inverted extensional grabens to the north; 3) basement thrust blocks in the south and 4) basement cored small ranges in the east. This foreland basin is located between two geological provinces: the Sierras Pampeanas and the Santa Bárbara system.Cretaceous Salta rifting extended southwards covering the entire eastern part of the province of Tucumán in NW Argentina. Syn-rift and post-rift deposits can be recognized in accordance with their architectural geometries. Foreland basin sediments progressively covered the rift deposits as the Andean orogen propagated towards the east.Despite some early studies, the Tucumán basin is poorly documented. For the present study, 44 sections of 2D seismic surveys amounting to more than 730 km were used to describe the structure and the depositional evolution of the basin. The present structure is the result of a long sequence of events that includes a compressional deformation during the Paleozoic, a rifting stage during the Cretaceous and a foreland stage during the late Cenozoic. Although tectonic inversion, which has played a role during the foreland stage since the Miocene, can be observed in many sectors of the basin, it is more prominent along the margins. Reactivation of old basement discontinuities and inversion of Cretaceous normal faults produced the compartmentalization of the foreland, giving rise to the present shape of the Tucumán basin. This evolution is recorded in the Neogene deposits. 相似文献
119.
120.
J. M. Diego † J. Silk W. Sliwa 《Monthly notices of the Royal Astronomical Society》2003,346(3):940-948
We cross-correlate WMAP and ROSAT diffuse X-ray background maps and look for common features in both data sets. We use the power spectrum of the product maps and the cross-power spectrum to highlight a possible correlation. The power spectrum of the product maps does not detect any correlation and the cross-power spectrum does not show any significant deviation from zero. We explore different explanations for this lack of correlation. A universe with a low value of σ8 could naturally explain the lack of correlation. We also discuss the systematic effects that can affect this result, in particular the subtraction of some cluster signal from the ROSAT diffuse maps, which could significantly suppress the correlation signal. These systematic effects considerably reduce the significance of our constraints on the cosmological model. When we include the systematic effects, we find a weaker constraint on σ8 , allowing models with values as large as σ8 = 1 (for Ωm = 0.3 ) to be consistent with the lack of correlation. To illustrate the capabilities of the method with future high-quality data, we show how from the correlation signal it should be possible to predict the level of contamination of the Sunyaev–Zel'dovich effect on the power spectrum of the cosmic microwave background. Within the systematic errors, we find evidence that this contribution is negligible for WMAP and is expected to be small in experiments like ACBAR or CBI, but can be important for future high-resolution experiments. 相似文献